Tool to measure power on 3-phase motors

[goe.di]

Hey all,
which tool do you use to measure power of three phase motors?

Or do you just take current readings on each phase + voltage readings and do the calculation by yourself?

Greatings,
Dirk

[CraziFuzzy]

Hey all,
which tool do you use to measure power of three phase motors?

Or do you just take current readings on each phase + voltage readings and do the calculation by yourself?

Greatings,
Dirk

simply reading voltage and current won't give you power (W). It will give you apparent power (VA). A power meter has to look at the phase shift between voltage and power to determine the actual power used. For this, the only thing to use is a power meter (usually installed as a fixed device, not generally used in a portable fashion)

There are 'portable' units available, but they are usually geared towards power quality analysis and datalogging.

[goe.di]

You are right it will give you apparent power but with an assumed cosPhi (0,85-0.9) you can "estimate" the real power. Heard from several people doing that.

So you just take amp draw readings to make sure that the "fixed" devices on 3-Phase motors show the right values?

How on one phase motors?

[Control Man]

Fluke 433 Three-phase Power Quality Analyzer